Like the title says....Ive been debating on taking the insert out of my factory GT hood scoop and trimmin out the hood to allow nice cold air under the hood. Is this a good idea or bad idea?
Is a true, functional hood scoop helpful?
LopnVrt
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I think he data logged IAT's. It seemed to take longer for the fan to kick on and took less time to cool off. A friend was helping me and we where just logging stuff for shits and giggles. Plus I'm sure it's not an exact science. I'm a little a shamed to admit after all this time I still can't data log. I have a lot of metal piping and it almost blew right on the SC.
You would probably have to data log under several different conditions for both hoods to get a more acurate number. I think datalogging IATs, water temps, exhaust temp and on and off fan cycles would produce the best results.
You would probably have to data log under several different conditions for both hoods to get a more acurate number. I think datalogging IATs, water temps, exhaust temp and on and off fan cycles would produce the best results.
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A lot of the aftermarker 2000 Cobra R and 1995 Cobra R hoods are not heat extracting hoods. A lot of them do not have vents by the windshild. I'm running a Cervini 19 Cobra R hood. It does.
If you make your hood scoop functional you will be pulling in rain. A few weeks ago a member mentioned that it filled his spark plug holes and shorted out is COPs.
If you make your hood scoop functional you will be pulling in rain. A few weeks ago a member mentioned that it filled his spark plug holes and shorted out is COPs.
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why not just cut out below the scoop and flip the scoop around? :dunno functional heat extractor? or no :tomato, i was thinking of doing that 
maybe; just not with the hood in my sig
maybe; just not with the hood in my sig 
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cant on thesewhy not just cut out below the scoop and flip the scoop around? :dunno functional heat extractor? or no :tomato, i was thinking of doing that
the scoop would it the plenum. the plenum is right behind the honey comb cut out of the hood.
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if thats the case he drove it threw a giant puddle and his coil boots need replacing.
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I have an ait guage so i seen the difference right away.
Also a cowl hood was not designed to pull heat out. it was actually designed to help force air into the engine(as long as it is sealed to the air cleaner).
I never get water on my engine when I wash it and I put duct tape over hole in hood leaving a small slit in center and never get water that way either when it rains(I live in Seattle!!!). if you don't take precautions when it rains it could very easily short the cops out with water intrusion
Also a cowl hood was not designed to pull heat out. it was actually designed to help force air into the engine(as long as it is sealed to the air cleaner).
I never get water on my engine when I wash it and I put duct tape over hole in hood leaving a small slit in center and never get water that way either when it rains(I live in Seattle!!!). if you don't take precautions when it rains it could very easily short the cops out with water intrusion
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well thats off my to do list lolcant on these
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I think you may have meant hood scoop. Yes, the original functional hood scoops forced air right to the carburator. My cowl hood is specifically designed to extract heat from the engine bay.
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No , i meant that,. factory has been doing that for a long time....camaro's, chevelles,etc. research cowl hoods and you'll see what i mean
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But Chevelles did have a trap door at the back of the hood that opened to help accomplish this. Most aftermarket cowl hoods are completely open in the back. I guess both could cause a vacuum at the back if they were sealed well. I could maybe see that maybe helping to pull air into the engine bay, but that would also extract some heat I would think.
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don't recall camaros having that.
if the air cleaner is sealed to the hood it does help a lot. that was the whole purpose of a cowl hood to begin with, to take advantage of the pressure area at the windshield. it was never DESIGNED to extract heat and could actually hurt by shoving heat back inTo be effective, a functional scoop must be located at a high-pressure area on the hood. For that reason, some functional scoops are located at the rear of the hood, near the vehicle's cowl, where the curvature of the windshield creates such a high-pressure zone, and may be placed so that their opening faces the windshield (a reversed scoop).
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A cowl hood IS designed to vent air out the back. That is one of the two main uses (#2 is to clear over sized intake set ups). The air moving over the hood creates vacuum at the rear of the hood. That vacuum pulls hot air out from under the hood.
You can see it when driving in the rain. Water dripping down the raised section at the back of the hood flys off and up over the windshield. It's not getting sucked in.
You can see it when driving in the rain. Water dripping down the raised section at the back of the hood flys off and up over the windshield. It's not getting sucked in.
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I have to disagree to an extent on that last comment. My 93 fox had a harwood 4 inch cowl hood and after i washed it i would always have to clean off my chrome carb breather and valve covers cause the water got sucked in. I could see it goin in. I always thought it was wierd that it never went to the windshield. BUT that was a fox body idk if it be different on the newer cars or not but i would think the same aerodynamics would apply? Maybe its different because the fox bodies didnt have a big grille?? The hood came down between the headlights and the air passin under car made a vacuum and pulled the water drops off the cowl idk
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the cowl area is a high pressure area, not a low pressure area. no suction is created. this is why your heater fan inlet is in this area. heat extractor hoods have there vents in a low pressure area like the 03-04 cobras
Also a lot of the so called cowl hoods in the after market are not "true" cowl hoods. a true cowl hood has the rear opening inch's from the windsheild
Also a lot of the so called cowl hoods in the after market are not "true" cowl hoods. a true cowl hood has the rear opening inch's from the windsheild
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My '69 Camaro had fake chrome vents. The Chevelles of the time were the same.
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original cowl induction system was optional on 1969 Camaros with 302 (Z-28), SS-350, SS-396, 427 (ZL-1) or the Cast Iron Block 427/425hp (COPO 9561) Camaros. The cowl induction system was also installed on dealership performance specials such as Yenko, Berger,Dana, Nickey or Baldwin-Motion.
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Limited is correct on the statement about a cowl hood. Look at any REAL drag car with a cowl hood and it will be sealed between the carb and the hood. theoretically, at speed, air moving across your hood is deflected by and over the windshield. the theory behind 'cowl induction' is that air reflects off the windshield and is sucked into the lower pressure area (into the hood) and provides more air under the hood helping alleviate under hood temperatures, provide cooler/denser air for intake, etc. most people use them for clearance problems, ie running big intake/carb/air cleaner and/or forced induction that require large air boxes and piping over the carburetor.
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Some Chevelles had a trap door that open also.
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Ok, maybe how we define cowls is different.
My 2000 has a 2 1/2 rise hood with vents at the rear (by the wiper cowl). As air flows past, that pocket cretaed behind it is low pressure (like the top trailing edge of an aircraft wing). Under my hood is high pressure - from being forced into the front while driving. High pressure under the hood and low pressure from swirling aft of the back edge of the cowl is pulling air out from under the hood (on my car) - so when I drive in the rain, I see water drops catching the airstream and going up over the car, not being pulled into the engine bay through the vent.
My 2000 has a 2 1/2 rise hood with vents at the rear (by the wiper cowl). As air flows past, that pocket cretaed behind it is low pressure (like the top trailing edge of an aircraft wing). Under my hood is high pressure - from being forced into the front while driving. High pressure under the hood and low pressure from swirling aft of the back edge of the cowl is pulling air out from under the hood (on my car) - so when I drive in the rain, I see water drops catching the airstream and going up over the car, not being pulled into the engine bay through the vent.
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maybe cowl hoods of todays cars are designed different since they are no longer carb on top and wont benefit from how the original cowl hoods worked. If you look at a circle track car with a cowl hood, they have and enclosed air cleaner with an opening in the back to benefit from the way that style cowl hood works
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